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Halfan Side Effects

Generic name: halofantrine

Medically reviewed by Last updated on Nov 29, 2023.

Note: This document contains side effect information about halofantrine. Some dosage forms listed on this page may not apply to the brand name Halfan.

Applies to halofantrine: oral tablet.


In rare cases, halofantrine may affect the heart, causing irregular heartbeats that could result in death. Do not take halofantrine if you have a heart condition such as an irregular heartbeats or a history of irregular heartbeats; a history of prolonged QT intervals; a family history of congenital long QT syndrome; heart block or other conduction disturbances; or unexplained episodes of fainting. These conditions may increase the risk of irregular heartbeats and death while taking halofantrine.

Take halofantrine on an empty stomach, at least one hour before or two hours after food. Taking halofantrine with food may increase the risk of irregular heartbeats.

Use caution when driving or performing other hazardous activities. Halofantrine may cause dizziness. If you experience dizziness, avoid these activities.

Stop taking halofantrine (the active ingredient contained in Halfan) and seek emergency medical attention or contact your doctor immediately if you experience any of the following serious side effects:

Other, less serious side effects may be more likely to occur. Continue to take halofantrine and talk to your doctor if you experience

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

For Healthcare Professionals

Applies to halofantrine: oral tablet.


Cardiovascular side effects have included QT interval prolongation, torsades de pointes, ventricular arrhythmias, and death. Chest pain and palpitations have been reported less than 1% of patients in clinical trials, and orthostatic hypotension has been reported in less than 1% to 33% of patients. Hypertensive crisis (1/933) and cerebrovascular accident (1/933) have been reported, although causality was not clearly established. Quinidine-like electrocardiographic changes have also been reported.[Ref]

Higher risk may be associated with larger than recommended doses, previous or concurrent mefloquine treatment, preexisting QT interval prolongation, or concurrent administration of other QT interval-prolonging drugs. Prolonged QTc interval has been reported in up to 81% of adults treated with standard halofantrine doses and in 100% of patients treated with high doses (72 mg/kg). Prolonged QTc interval has been reported in 50% of children and prolonged PR interval has been reported in 38% of children (n=21). Females may have a higher risk of adverse cardiovascular effects.

It has been proposed that halofantrine prolongs repolarization by blocking HERG potassium channels.[Ref]


Gastrointestinal (GI) side effects have included abdominal pain (8.5%), diarrhea (6%), vomiting (4.3%), and nausea (3.4%), although these symptoms may also occur with a malarial infection. Abdominal distention, anorexia, constipation, dyspepsia, and stomatitis have been reported in less than 1% of patients. GI upset has also been reported.[Ref]


Hematologic side effects have included decreased hematocrit, decreased or increased white blood cells, decreased platelet counts, hemolysis, and hemolytic anemia. These reactions may also occur with a malaria infection.[Ref]


Hypersensitivity side effects have included allergic and anaphylactic reactions including facial edema and urticaria.[Ref]


Dermatologic side effects have included pruritus (2.6%) and rash (less than 1%).[Ref]


Musculoskeletal side effects have included rigors (1.7%), myalgia (1.3%), arthralgia (less than 1%), and back pain (less than 1%).[Ref]

Nervous system

Nervous system side effects have included dizziness (4.5%) and headache (3%). Asthenia, confusion, convulsions, depression, paresthesia, and sleep disorder have been reported in less than 1% of patients.[Ref]


Genitourinary side effects have included urinary frequency (less than 1%).[Ref]


Ocular side effects have included abnormal vision (less than 1%).[Ref]


Respiratory side effects have included cough (3%). Pulmonary edema has been reported (1/933); however, causality was not determined.[Ref]


Other side effects have included fatigue, malaise, and tinnitus in less than 1% of patients.[Ref]


Hepatic side effects have included increased hepatic transaminases, which returned to normal within 2 to 3 weeks.[Ref]


Renal side effects have included blackwater fever (acute intravascular hemolysis with acute renal failure and hemoglobinuria) requiring hemodialysis patients taking halofantrine (the active ingredient contained in Halfan) for Plasmodium falciparum infections (n=2). Causality was not clearly established. One patient had a positive Coombs test.[Ref]


1. (2021) "Product Information. Mefloquine Hydrochloride (mefloquine)." Hikma USA (formerly West-Ward Pharmaceutical Corporation)

2. (2003) "Product Information. Halfan (halofantrine)." GlaxoSmithKline

3. Nosten F, ter Kuile FO, Luxemburger C, et al. (1993) "Cardiac effects of antimalarial treatment with halofantrine." Lancet, 341, p. 1054-6

4. (2001) "Sudden death in a traveler following halofantrine administration--Togo, 2000." MMWR Morb Mortal Wkly Rep, 50, 169-70, 179

5. (2001) "From the Centers for Disease Control and Prevention. Sudden death in a traveler following halofantrine administration--Togo, 2000." JAMA, 285, p. 1836

6. Karbwang J, Na Bangchang K (1994) "Clinical pharmacokinetics of halofantrine." Clin Pharmacokinet, 27, p. 104-19

7. Touze JE, Heno P, Fourcade L, et al. (2002) "The effects of antimalarial drugs on ventricular repolarization." Am J Trop Med Hyg, 67, p. 54-60

8. Mbai M, Rajamani S, January CT (2002) "The anti-malarial drug halofantrine and its metabolite N-desbutylhalofantrine block HERG potassium channels." Cardiovasc Res, 55, p. 799-805

9. Sahr F, Willoughby VR, Gbakima AA, Bockarie MJ (2001) "Apparent drug failure following artesunate treatment of Plasmodium falciparum malaria in Freetown, Sierra Leone: four case reports." Ann Trop Med Parasitol, 95, p. 445-9

10. Abernethy DR, Wesche DL, Barbey JT, et al. (2001) "Stereoselective halofantrine disposition and effect: concentration-related QTc prolongation." Br J Clin Pharmacol, 51, p. 231-7

11. Sowunmi A, Fehintola FA, Ogundahunsi OA, Ofi AB, Happi TC, Oduola AM (1999) "Comparative cardiac effects of halofantrine and chloroquine plus chlorpheniramine in children with acute uncomplicated falciparum malaria." Trans R Soc Trop Med Hyg, 93, p. 78-83

12. White NJ, Pukrittayakamee S (1993) "Clinical malaria in the tropics." Med J Aust, 159, p. 197-203

13. Piippo K, Holmstrom S, Swan H, et al. (2001) "Effect of the antimalarial drug halofantrine in the long QT syndrome due to a mutation of the cardiac sodium channel gene SCN5A." Am J Cardiol, 87, p. 909-11

14. Toivonen L, Viitasalo M, Siikamaki H, Raatikka M, Pohjola-Sintonen S (1994) "Provocation of ventricular tachycardia by antimalarial drug halofantrine in congenital long QT syndrome." Clin Cardiol, 17, p. 403-4

15. Winstanley P (1998) "Malaria: treatment." J R Coll Physicians Lond, 32, p. 203-7

16. Ezeamuzie IC, Igbigbi PS, Ambakederemo AW, Abila B, Nwaejike IN (1991) "Halofantrine-induced pruritus amongst subjects who itch to chloroquine." J Trop Med Hyg, 94, p. 184-8

17. Vachon F, Fajac I, Gachot B, Coulaud JP, Charmot G (1992) "Halofantrine and acute intravascular haemolysis." Lancet, 340, p. 909-10

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.